If you were a lawyer in court trying to prove that Slovakia's 6-0 loss to Denmark on May 14 was not the most shockingly lopsided loss ever by a “Big Seven” country to a non-elite hockey nation at the elite level, you'd have a tough task.
If we take as our conservative benchmark a modern-era loss by four or more goals by a “Big Seven” country (Canada, Czech Republic, Finland, Russia, Slovakia, Sweden, or the United States) to a country that clearly belongs in a lower echelon, there are very few examples in the World Championships, Olympics, or Canada Cup/World Cup of Hockey tournaments.
If the Japanese had beaten the Soviets 5-1 at the 1980 Olympics, for instance, that would surpass the Danish win over Slovakia in terms of surprise value. (However, they actually lost 16-0.)
“Modern-era” is an important term to keep in mind. For instance, when Switzerland beat Finland 12-0 on February 16, 1952, that might sound like it fits the criteria.
However, the IIHF has previously dated the start of the modern era in hockey to the 1954 World Championship in Sweden, where the Soviet Union captured its first-ever gold. Moreover, Swiss hockey was in many respects riding an all-time high in the early 50s, although the bubble was soon to burst. To put things in context, the Swiss won Worlds bronze in 1950, 1952 and 1953, while the Finns were participating in their first Olympic hockey tournament in 1952, and had finished close to the bottom of the standings in their three previous Worlds (1939, 1949, 1951).
So that 12-0 walloping doesn't really fit the bill.
Your best bet as a lawyer? Point to Germany's 7-1 win over the Czech Republic at the 1996 World Cup of Hockey. With due regard to winning German goalie Josef “Peppi” Heiss and defenceman Jan Benda, who led the offence with two goals, there was no way in the world the Germans should ever have been able to thoroughly outgun a Czech roster that came loaded with Jaromir Jagr, Robert Reichel, Martin Straka, Jiri Dopita, and many other aces.
Remember, too, that these same Czechs formed the core of the soon-to-be greatest run in their nation's history, where they won Olympic gold in 1998 and three straight Worlds between 1999 and 2001.
Now in fairness, also remember that the Germans were long regarded as the number seven or eight hockey team in the world, winning Olympic bronze in 1976 and securing an invitation to the 1984 Canada Cup under the flag of West Germany. Denmark, meanwhile, only returned to the elite division of the World Championship in 2003 after a 54-year absence.
Nonetheless, it's not hard to argue that the '96 Czech team was superior in all respects to the Slovak team that just got clobbered by the Danes.
Other examples are frankly pretty weak. They mostly feature underwhelming, probably undermotivated American rosters losing in Relegation Round action.
For instance, on April 21, 1981, West Germany thumped the United States 6-2. The biggest names the U.S. iced there included “Miracle on Ice” vets Dave Christian, Mark Johnson, and Mark Pavelich, as well as future U.S. head coach Ron Wilson and defenceman Reed Larson, who scored 20-plus goals in six of his NHL seasons. On May 10, 1998, the Americans fell 4-0 to Italy, despite the presence of Bryan Smolinski and (pre-NHL) Chris Drury.
The 7-2 loss by the United States to West Germany on March 25, 1971 wasn't in relegation play, but few names on that U.S. roster would be familiar to non-hardcore hockey fans, apart from future Penguins GM Craig Patrick and perhaps journeyman NHLer Henry Boucha.